In recent years, attention has been paid to dye-sensitized solar cells as photoelectric conversion devices, since high photoelectric conversion efficiency may be obtained at low cost.
A dye-sensitized solar cell generally includes a working electrode, a counter electrode, a photosensitizing dye that is supported in the working electrode, and an electrolyte that is disposed between the working electrode and the counter electrode.
In regard to such dye-sensitized solar cells, there is a demand for a further improvement in the photoelectric conversion characteristics, and various studies are in progress for that purpose.
For example, Patent Document 1 discloses a dye-sensitized solar cell which includes a glass substrate; an electrode that is provided on the back surface of the glass substrate; a light absorbing particle layer that is formed on the lower surface of the electrode by depositing semiconductor fine particles having a particle size of 80 nm or less and having a dye adsorbed thereto; an electrolyte section that includes the light absorbing particle layer and is provided on the lower surface of the electrode; a counter electrode that is provided on the lower surface of the electrolyte section; a high refractive index material thin film that is provided between the electrode and the light absorbing particle layer; and a light reflecting particle layer that is provided on the lower surface of the light absorbing particle layer and is formed by depositing a high refractive index material particles having a particle size of 200 nm to 500 nm. In this dye-sensitized solar cell, when sunlight is transmitted through the glass substrate, the electrode and the high refractive index material thin film, and enters the light absorbing particle layer, the light that is transmitted through the light absorbing particle layer is reflected at the light reflecting particle layer, and of the light that has been reflected at the light reflecting particle layer, the portion of light that is transmitted through the light absorbing particle layer and returned to the high refractive index material thin film is totally reflected at the high refractive index material thin film.
As a result, light is entrapped in the light absorbing particle layer, and an enhancement of the photoelectric conversion characteristics is promoted.
Patent Document 1: Japanese Patent Application Laid-Open (JP-A) No. 10-255863